Local Model Update

RMSTM offers best in class functionality which allows for the local updating of the geological property model. Combined with the existing local grid updating capability, it provides reservoir modellers with a quick and robust tool to update 3D models around a local area; for example, when new well data becomes available.

Local Model Update

This pragmatic approach to model updating is particularly useful when time is of the essence. In cases where a 3D model has been painstakingly built and a history match achieved, it provides a way to maintain the reservoir model “live” and current at all times, avoiding the need to perform the full 3D modelling workfl ow each time new data is available.

Local update of the 3D grid has been available since RMS version 8.0 (Nov 2006). Based upon new structural horizons, or a difference map, the 3D grid can be locally adjusted to new wells without the need to rebuild the structural framework. More signifi cantly, it also retains the existing property models, which can also be updated.

Local update is available for a number of the facies modellingmethods and the petrophysical modelling, including:

• Facies: Channels• Facies: Composite• Facies: Indicators• Facies: Multipoint• Petrophysical Modelling

IN SUMMARY

• Local update of structure, facies and petrophysical models.

• Keep reservoir models live and up-to-date at all times.

• Adjustment area fully controllable by users, polygon or variogram.

• All parameters changed, including 3D grid structure, facies & petrophysical parameters.

• Unique advanced algorithms produce models which are geologically robust, without any ‘patchwork’ effects.

• Allows users to incorporate all latest reservoir data, without the need to perform a fi eld wide history match each time.

• Local model updating allows RMS users to make much more effi cient use of resources, and therefore make better decisions based on all available data.

Facies updated in region around new well

New well shows low NTG compared to 3D model

Petrophysics updated in region around new well

ORIGINAL

ROXAR AS, GAMLE FORUSVEI 17, PO BOX 112, 4065 STAVANGER, NORWAY TELEPHONE +47 51 81 8800 FAX +47 51 81 8801 WWW.ROXAR.COM

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2014

Local Model Update

Object Modelling

The updating algorithm will make minimal changes to the existing model whilst conditioning to the new well data. This is done by attempting to make existing objects match the new, mismatched data. Only in cases where this is impossible are new objects generated, helping to ensure that the fi nal volume fraction is as close as possible to the original.

Indicator/Multipoint

Options for indicator and multipoint based updating is also available. In addition to being used to update existing indicator/multipoint models, this approach can be used to update any discrete parameter with new well observations. It could, for example, be used to update an object based model. The user has the option of either specifying the region or area where the update is to be made, or this can be automatically calculated by the update algorithm based upon the well observations, original model, and variogram range. The algorithm ensures an accurate match not just to the new well data, but also the statistics of the existing model, including smooth integration into the existing realisation.

Petrophysical Modelling

Petrophysical property models such as porosity and permeability can also be locally updated; with or without the associated facies model. As with indicator modelling, the update region can either be automatically calculated, or user defi ned. The user may opt to choose the original and updated facies models as input. Other model settings will typically remain unchanged but could also be updated if required. The fi nal result is then created as a weighted average of the initial petrophysical model and a newly simulated model.

To learn more please visit www.roxarsoftware.com or emailus on rss.marketing@emerson.com.

Original Updated

Indicator Model

Local update example using

channel sands. In this example

the original model (left) is not

based upon the new well data

(shown in red) . The updated

model (right) with the adjusted

channel objects. The updates

for the upper most observed

channel can be seen in the

image above, where the

adjusted channel is shown with

grid lines.